In her math class, Vanessa took 6 quizzes. Her scores were 97, 78, 91, 86, 80, and 90. What was her average score on the quizzes?
Solution: The average is the sum of her scores divided by the number of scores. There are 6 scores and their sum is $97 + 78 + 91 + 86 + 80 + 90 = 522$ Her average score is $522 \div 6 = 87$.